藏鸡垂体GH基因克隆、时序表达及与屠宰性能的关联研究

Study on Tibetan Chicken Pituitary GH Gene Cloning,Temporal Expression and Correlation with Performance of Slaughter

【目的】为研究垂体GH基因对藏鸡屠宰性能的影响。【方法】以藏鸡为研究对象,利用RT-PCR技术克隆藏鸡GH基因,并进行生物信息学分析,利用荧光定量PCR检测GH基因在藏鸡不同发育阶段脑垂体中的表达谱,并与119日龄藏鸡屠宰性能进行关联分析。【结果】藏鸡GH基因长1029 bp,开放阅读框651 bp,编码216个氨基酸。与原鸡比较,核苷酸同源性为99%,存在7个核苷酸突变位点,不存在氨基酸变异;与火鸡比较,核苷酸同源性为94%,存在25个核苷酸突变位点,有7个氨基酸的差异,且在物种间进化上具有较高的保守性。GH基因在藏鸡81、119、154、210 d 4个发育时期的脑垂体中均存在表达,在81 d时表达量最高,极显著高于其他发育时期(P <0. 01),其余3个时期之间无显著差异,且不存在明显的性别差异。相关分析发现,垂体GH基因的表达与119日龄公藏鸡的活体重、屠体重、半净膛、全净膛等性状均呈正相关,其中与屠体重和半净膛的相关性达到了显著水平(P <0. 05),与腿肌重、腿肌率及胸肌率均呈负相关;与119日龄母藏鸡活体重、屠体重、半净膛、全净膛等屠宰性状均呈正相关,与屠宰率、半净膛率、胸肌率及腿肌率均呈负相关。【结论】本研究结果表明垂体GH基因的表达水平可能直接影响藏鸡早期生长发育。

[ Objecttive] This study was to get the effect of pituitary GH gene on the slaughter performance of Tibetan chicken. [ Method] The GH gene of Tibetan chicken was cloned by RT-PCR and analyzed by bioinformatics method and the GH gene was detected by fluorescence quantitative PCR. [ Result] The GH gene of Tibetan chicken was 1029 bp length and 651 bp in open reading frame, encoding 216 amino acids. Compared with the original chicken, nucleotide homology is 99 %, there were 7 nucleotide mutation sites, there was no amino acid variation ; Compared with tin＇key, the nucleotide homology was 94 %, there were 25 nucleosides mutation sites. There were seven amino acid differences, and the evolution of species is highly conserved. The GH gene was expressed in the pituitary gland of Tibetan chicken at four de- velopmental stages （81, 119, 154 and 210 days）. The expression level of GH gene was the highest at 81days, significantly higher than that at other developmental stages （ P 〈 0.01 ）. There was no significant gender difference. Correlation analysis showed that the expression of pi- tuitary GH gene was positively correlated with the live body weight, carcass weight, semi-evisceration and whole evisceration of 119-day-old Tibetan cock, and the correlation with the carcass weight and semi-evisceration reached a significant level （ P 〈 0.05 ） , negatively correlated with leg muscle weight, leg muscle rate and breast muscle rate; The expression of pituitary GH gene was positively correlated with the live body weight, carcass weight, semi-evisceration and whole evisceration in 119-day-old Tibetan hen, which was negatively correlated with the slaughter rate, half evisceration rate, breast muscle rate and leg muscle rate. [ Conclusion] The results of this study indicate that the expression of pituitary GH gene can directly affect the early growth and development of Tibetan chicken.